Air-supported structure



Dec. 1, 1964 K. P. COHEN ETAL 3,159,165

AIR-SUPPORTED STRUCTURE 2 Sheets-Sheet 1 Filed April 21, 1961 Kenne'fh Paul Cohen C harles H. RCorbei' I INVENTORS 2 Sheets-Sheet 2 Filed April 21. 1961 Kennei'h Pau] Cohen Charles HRCorbef'i' IN VHV TORS United States Patent 3,159,165 Alfifillllflk'lfil STRUCTURE Kenneth Paul Qohen and Qharles A. R. Corbett, Portland, Greg assignors to Plastisnayd Corporation, Portland, Greg, a corporation of Gregor:

Filed Apr. 21, 1961, Ser. No. 1%,720 l @lairns. (Cl. 135-1) This invention relates to shelters or enclosures, and more particularly to improvements in shelters or enclosures that rely on pressurized air for their support.

Air-supported enclosures have a number of unique advantages. They are relatively easily taken down and transported from one location to another. In their collapsed state they are light and have little bulk in comparison with other shelters. When made of transparent material, during the day full illumination of their interiors is possible with sunlight. Such shelters when properly constructed are capable of withstanding relatively severe weather conditions, while rendering complete protection for anything within their confines.

A general object of the invention is to provide a novel air-supported shelter capable of manufacture from inexpensive and readily available plastic materials, that includes novel means providing protection from overinfiation.

A related object is to provide a shelter where the infiation thereof is determined by the volume encompassed by the shelter, as compared to the pressure of the air within. 7

Another object is to provide a shelter having improved means for anchoring the base thereof to the ground. In a shelter where it is desired that the volume encompassed by the shelter determine the amount of its inflation, the anchoring of the base of the shelter is particularly important, as looseness or play at the base has the detrimental eiiect of varying the volume encompassed by the shelter independently of conditions that should be controlling.

A further object is to provide a shelter with improved the shelter, and improved means for people to enter and leave the shelter.

A further object is to provide a form of shelter that may be manufactured in a number of sizes, without changing the size oi various components used in the construction of the shelter.

Another object is to provide an air-supported shelter with improved means for sealing the shelter whereby air losses may be maintained at a minimum.

Other objects and advantages will become more fully apparent, as the following description is read in conjunction with the accompanying drawings, wherein:

FIG. 1 is a top plan view of an inflated enclosure or shelter as contemplated in an embodiment of the invention, with portions of the enclosure removed so as to illustrate details;

MG. 2 is an end View of the enclosure in FIG. 1;

FIG. 3 is a cross section, somewhat enlarged, taken along the line 3-3 in FIG. 1;

FIG. 4 is a View, also enlarged, taken along the line 4-4 in FIG. 1; a

FIG. 5 is a view, also enlarged, of the outside and base of the enclosure, generally taken along the line 55 in FIG. 1; I

FIG. 6 is a cross sectional view, taken along the line 6-6 in FIG. 5;

FIG. 7' is a perspective view of a door frame with doors provided for entering and leaving the. enclosure, somewhat enlarged from the illustration of the door frame in FIG. 1;

FIG. 8 is an enlarged, cross sectional view, taken means for supplying air under pressure to the inside of along the line 8-8 in FIG. 1, showing details of a blower employed in inflating the enclosure; and- FIG. 9 is a cross sectional view, taken along the line 9-9 in FIG. 1, and enlarged, illustrating mechanism controllingthe blower and connected to a girth band provided in the construction.

Referring now to the drawings, especially FIG. 1, an air-supported structure is illustrated that comprises an expansive flexible sheet 10, forming the sides and roof of an enclosure, indicated generally at 12. In its operative, inflated condition, as shown in the figure, sheet 10 forms an enclosure with sides and a ceiling or roof that join with each other over expanses of smooth curvature. This tends to produce equalizing of pressures within the enclosure acting upon its roof and sides. Thus, in the embodiment illustrated, the enclosure at its ends and along its base has an outline that is approximately semicircular, and viewing a transverse cross section of the enclosure, the sides of the enclosure join with the roof over an arouate sweep that is also approximately semicircular. A factor in controlling the inflation of the shelter is that a transverse cross section of the shelter between its ends have a profile devoid of concavity.

Sheet 1% preferably is made of a plastic material, a clear polyvinyl chloride plastic being entirely satisfactory. With such a plastic, separate panels may be joined together by overlapping edges and then electronically welding aseam, to make the larger sheet 10. Panels in the sheet it) have been so joined, and are indicated in the drawings at 14.

The shelter is inflated with air by means of an intermittently operated blower mechanism indicated generally at Ell, Blower mechanism 29 includes a motor 22 driving a squirrel cage blower (not shown) enclosed in a housing indicated at 24. At 26 there is indicated an outlet for the blower, such outlet extending along the ground and having an opening indicated at 28. The opening preferably is opened and closed, during operating and nonoperating periods of the blower means, respectively, by a flapper valve 30. Gravity and inside air pressure normally hold valve 30 in a lowered, closed position when the blower mechanism is not operating, but the flapper valve swings up to open outlet 26 during operating periods for mechanism 24, with air then being expelled from the outlet into the interior of the shelter.

A means of entering and leaving the shelter is provided by a door means (see FIG. 7), which may be made of wood, fiberglass or other rigid or semirigid material. This comprises a door frame 41, defining a vestibule, with operable doors 42, 44 mounted on the door frame and closing off the ends of the vestibule. In entering the enclosure, for instance, a person may first open the outside door 44, while keeping inside door 42 closed, and then enter the vestibule. The outside door is then closed, and inner door 42, opened, to permit actual entry into the shelter. Thus, a form of air lock is provided, useful in minimizing air losses.

A feature of the invention is the provision of blower mechanism and door means that are separate from sheet lil of the enclosure, and a sheet It? of the enclosure that when fastened or anchored to the ground has a base that extends along the ground and over the blower outlet and door means with such base being sealed along its length to the ground, outlet, and door means so that the air is prevented from escaping from the enclosure. With such a construction, various sizes of blower mechanisms and 7 door frames may be used, without materially changing the construction orshape of sheet 19. Also, replacement of various parts is facilitated.

Considering now the manner in which the enclosure is anchored to the ground, and with reference now to FIGS. 5 and 6, thebase of the enclosure is indicated at 50. This extends along the ground and passes up and over the blower outlet and door frame where these are located. As can be seen in FIG. 7, at the location of the door frame base 5% is recessed at Slia to receive the door frame. No special recess in the base is usually needed for outlet 26 (see FIG. 4), as such can be made with a height so minor that a straight portion of the base at the location of the outlet fits snugly down on the outlet (the outlet may have sloping sides such as sides 26a to increase snugness of fit).

Along the base of the enclosure (including where it extends over the door frame), and secured to sheet ld, is an elongated sleeve means as. Such may be made, for instance, by folding over an elongated strip of material 61, and welding adjacent edges of tne strip together, and to the sheet 1d of the shelter. lnside sleeve means as is a passage 63:, and an elongated cable or line 64 is mounted within the passage. The cable is a member of substantially fixed length, and extends completely about the base of the shelter, including over the door frame and over the outlet of the blower mechanism.

At intervals. along sleeve means 6t), apertures 62 are provided. At the location of the apertures, portions of the cable or line 64 mounted within the sleeve means are exposed. Such exposed portions of the cable are fastened to the ground as by hook fasteners as. In the case of a swimming pool having a concrete apron, the fasteners may be screwed into anchor fittings ots'embedded in the apron.

An air seal is provided along the base of the enclosure by a flap means or fiap 7a. In the embodiment illustrated, flap means id for the most part is merely an extension of the sides of the enclosure that turns inwardly at the base of the enclosure and rests on the ground. The flap means rests loosely, it being the cable that serves to hold the enclosure solidly in place. Air pressures within the enclosure tend to urge the flap into snug ground contact, so that it effectively inhibits air leakage from within the shelter.

Flap 7o extends not only along the ground, but also over the outlet of the blower mecnanism and over door frame 41. At the location of the door frame, the flap may be made somewhat larger than the remainder of the iiap (as illustrated by portion 7% in FIG. 7) and given a somewhat rectangular outline and funnel shape, so that it roughly corresponds to the outline of the door frame.

At the location of the door frame, in a preferred embodiment of the invention, a cable Sh is provided in addition to cable 64. Cable 3t extends over flap portion "it a, has ends anchored to the ground, and is spaced laterally inwardly from cable 64. By using two laterally spaced cables at the door frame, assurance is given that the door frame be secured solidly in place. Cable 8% also con tributes to a better seal of flap 7% with the door frame.

As already mentioned, a plastic material preferably is used for sheet ll since plastic is light and relatively inexpensive. In warm weather, howe er, air pressures that on cooler days would keep the shelter properly inflated, tend to be excessive and cause stretching and over expansion of the shelter. Thus, a feature of the invention is the provision of a girth band or control line 9% (see FIG. 1) extending over the top and outside of the shelter, which is operatively connected to the blower mechanism, and determines the operating periods of the mechanism. By using the girth band, the extent that the shelter is inflated is determined by the volume encompassed by the shelter, and not by the pressure of air within it.

Girth band fill may take the form of a line such as a light, nonstretchable cord. it is shown asextending transversely of the shelter at a location about midway between its ends. The band rests on the shelter, and because of the'lack of concavity in the profile of the shelter where the band is supported, contacts the shelter along substansecured to the ground, having a flange 5'8 and a flange res. Between these flanges is a spring 162, with one end seated on the underside of flange 98, and the other end seated on a washer 194 secured as by a cotter pin 1&5 to an eye stud 1%. Eye stud 1% is mounted for up and down movement in flanges res, 102. Girth band 9t! is secured to the top of the eye stud res and the bottom of the eye stud abuts the actuating plunger of switch 94 (the body of the switch being secured to bracket 96). Conductors ill connect the blower mechanism and switch 94.

Spring tee resists upward movement of the eye stud,

. such as iscaused by enlargement of the shleter and tentially its entire length. One end of the band is anchored sioning of the girth band. On the shelter reaching a certain size, the girth band pulls eye stud ltld upwardly, with switch 1 4 being actuated as a consequence. The switch is connected to the blower mechanism, so that on actuation of the switch by upward movement of the eye stud, the blower motor shuts oif. With the eye stud in its lowered position (the position shown) the blower motor is turned on.

Note that preferably a girth band extending transversely of the shelter intermediate its ends is selected. A band so positioned has been found to indicate most accurately conditions of overinfiation in the shelter, without being overly sensitive to changes in shelter shape caused by factors that are not connected with the extent of infla tron.

Since inflation of the shelter is determined by the vol ume the shelter encompasses, pressures within the shelter area subject to some variation. The shelter may, under severe climatic conditions, particularly if pressures within the shelter are low, flap and strain in such a way as to damage itself. To prevent this, a mercury switch 112 is mounted within an envelope 11 provided in the top of the shelter near its center (see FIGS. 1 and 3), and this switch is connected by conductors 115 to an electrically operated buzzer or signaling device 118 positioned at a convenient warning location. The mercury switch is designed so that when the top of the shelter inclines a certain amount, for instance 10 from horizontal, the switch closes and the buzzer is energized. Thus, the switch constitutes slope-responsive means. By including the warning system described, a person may be made aware of hazardous conditions having been reached in the shelter, and can take appropriate action.

It is important in the organization that a line such as cable 64 be employed for anchoring the base of the shelter, since the cable has a substantially fixed length, and holds the base of the shelter without 'looseness or play existing. Thus, any changes in the tensioning of the girth band tends to be directly the result of changes in the extent of inflation of the shelter. Were looseness' present, undesirable overregulation of the blower motor could occur.

While an embodiment of the invention has been described, variations are possible without departing from the invention. It is desired to cover all modifications and variations that would be apparent to one skilled in the art and that come within the scope of the appended claims.

it is claimed and desired to secure by Letters Patent:

1. An air-supported structure comprising an expansive flexible sheet forming the sides and roof of anenclosure, an elongated girth band extending over the top and down the sides of the enclosure, intermittently operated blower means for inflating the enclosure, means operatively connecting the girth band and blower means whereby the operating periods of the blower means are regulated by said girth band, a power-operated signaling device, sloperesponsive means mounted on a portion of said enclosure sensitive to a change in the slope therein, andmeans connecting said slope-receiving means and power-operated signaling device whereby upon a change in the slope of said portion of said enclosure occurring said signaling device is actuated.

2. The enclosure of claim 1 wherein said slope-responsive means comprises a switch enclosed within an envelope, and said switch is mounted on the roof of said enclosure.

3. An air-supported structure comprising an expansive flexible sheet means forming an enclosure, means for inhating the enclosure, means controlling the means for inflating the enclosure whereby the enclosure is maintained at substantially constant volume, a power-operated signalling device, slope-responsive means mounted on a portion of said enclosure sensitive to a change in the slope therein, and means connecting said slope-responsive means and power-operated signaling device whereby upon a change in the slope of said portion of said enclosure occurring said signaling device is actuated.

4. An air-supported structure comprising an expansive flexible sheet forming the sides and roof of an elongated enclosure,

said sides and roof smoothly joining with each other over expanses of smooth curvature,

said sheet having an outer side that extends from one side of the enclosure up and over the roof of the enclosure to the other side that is substantially devoid of concavity,

an elongated transversely extending girth band resting on the outer side of said sheet, and extending over the roof and down the sides of the enclosure where said outer side of the sheet is devoid of concavity,

intermittently operated blower means for introducing air to the enclosure thus to inflate it, and operatively connected to the girth band with the girth band controlling operating periods of the blower means,

a power-operated signaling device, 7

slope-responsive means mounted on said flexible sheet adjacent said girth band sensitive to a change in the slope of the sheet, and

means connecting said slope-responsive means and power-operated signaling device, whereby upon a change in the slope of said slope-responsive means produced by movement of said flexible sheet said signaling device is actuated.

References Cited by the Examiner UNITED STATES PATENTS 1,302,182 4/19 Lanchester 1351 X 2,335,300 11/43 Nefif 135-1 X 2,754,497 7/56 Wolpert 340279 2,914,776 12/59 Hotz 135-1 X 2,930,467 6/60 Meyer et al. 135--1 2,948,286 8/60 Turner 1351 3,059,655 10/62 Bird 135-1 HARRISGN R. MOSELEY, Primary Examiner.

I. D. SEERS, Examiner. 

1. AN AIR-SUPPORTED STRUCTUR COMPRISING AN EXPANSIVE FLEXIBLE SHEET FORMING THE SIDES AND ROOF OF AN ENCLOSURE, AN ELONGATED GIRTH BAND EXTENDING OVER THE TOP AND DOWN THE SIDES OF THE ENCLOSURE, INTERMITTENTLY OPERATED BLOWER MEANS FOR INFLATING THE ENCLOSURE, MEANS OPERATIVELY CONNECTING THE GIRTH BAND AND BLOWER MEANS WHEREBY THE OPERATING PERIODS OF THE BLOWER MEANS ARE REGULATED BY SAID GIRTH BAND, A POWER-OPERATED SIGNALING DEVICE, SLOPERESPONSIVE MEANS MOUNTED ON A PORTION OF SAID ENCLOSURE SENSITIVE TO A CHANGE IN THE SLOPE THEREIN, AND MEANS CONNECTING SAID SLOPE-RECEIVING MEANS AND POWER-OPERATED SIGNALING DEVICE WHEREBY UPON A CHANGE IN THE SLOPE OF SAID PORTION OF SAID ENCLOSURE OCCURRING SAID SIGNALING DEVICE IS ACTUATED. 